Vitamins and minerals

Folate, also known as vitamin B9, plays a crucial role in many important functions in the body. Folic acid is the supplement form of folate. One of its primary functions is to support healthy cell growth and division. It is essential for the formation of DNA and RNA, which are the building blocks of cells. Folate also helps to produce red blood cells and is necessary for proper brain function. Additionally, folate has been shown to reduce the risk of stroke and heart attacks, as folate helps to lower levels of homocysteine, a compound that can damage the inner walls of arteries.  

The recommended daily intake for adults 19 years and above is 400 micrograms (µg) of dietary folate equivalents (DFE). In pregnancy, the recommendation increases to 600 µg DFE per day. 

Some health conditions, such as rheumatoid arthritis require a much higher dose of folate, due to taking the medication methotrexate. For those taking methotrexate, generally 5 mg of folic acid is taken weekly four days after taking methotrexate. To help remember this, some people use the alliteration tactic: “Methotrexate Monday, folic acid Friday”.

Folic acid is about 85% bioavailable (the extent to which the nutrient is available to its intended destination) in the form of supplements and folic acid used to fortify foods. Folate found in food is about 50-60% bioavailable. 

Supplementation of folic acid while taking methotrexate has been found to decrease the risk of side effects such as nausea, vomiting, mouth ulcers and liver toxicity. This is because methotrexate is a folate antagonist, which means it stops cells in our body from using folic acid to make DNA.

It depends on where you are getting your folate from. There are no issues with high amounts of folate from food, but high levels from supplements can cause some concerns.

High amounts of folic acid can also mask symptoms of B12 deficiency or make it worse. 

The Upper Level in New Zealand for healthy adults is 1 mg (1000µg) of folic acid daily. Those on methotrexate will have a higher upper level and this should be guided by your rheumatologist or specialist. 

Methotrexate, a common drug used in inflammatory forms of arthritis, lowers folate in the body, so doctors should prescribe a folic acid supplement to people taking methotrexate. Folic acid supplementation can help to reduce side effects.

For pregnant women and those planning to conceive, folate supplementation is particularly important as it can help reduce the risk of neural tube defects at birth.

If you have a folate deficiency, this can progress to a form of anaemia which can cause weakness, fatigue, irritability and heart palpitations. In these cases, folic acid supplementation is required to stimulate production of red blood cells.

If you think you may need to supplement with folic acid, talk to your GP first.

• From food: dark green leafy vegetables (taro leaves, Chinese greens, turnip leaves, spinach, romaine lettuce) asparagus, Brussels sprouts, broccoli), legumes (kidney beans, lentils etc.), peanuts, sunflower seeds, fruit, fruit juices, whole grains, liver, seafood, eggs, fortified foods such as bread in New Zealand
• Supplements: folic acid can be prescribed in 800 µg or 5 mg doses. You can also get a variety of doses over the counter at pharmacies, health stores, supermarkets and online. However, always check with your GP or specialist before starting or increasing any folic acid supplements

Vitamin D is a fat-soluble vitamin made in the skin when it is exposed to sunlight. There are two types of Vitamin D. D3, or cholecalciferol, is produced by mammals and fish, and D2, or ergocalciferol, exists in plants. 

During the winter months, it is especially important to spend time outside to expose your skin to the sun in order to make enough Vitamin D, as we generally make less due to less sunshine hours and covering more skin with warm clothes. Of course, in New Zealand it is best to wear sunscreen if you are outside for long periods of time.

The primary role of Vitamin D is to support adequate blood calcium levels by improving the small intestine’s ability to absorb calcium from the diet. It is involved in bone health, mood, and immunity, helping to maintain healthy skin and muscle strength.

Children and adolescents from 0-18years, and adults 19-50 years old should get 5.0 micrograms (µg) daily, or 200 International Units (IU). Adults 51-70 years need 10µg per day, and those over 70 years need 15 µg or 600 IU daily.

Supplements are in D2 or D3 form. There is evidence that D3 may increase blood levels better than D2. Many people will get adequate amounts through skin exposure to the sun and won’t need to supplement. However, those who always wear protective clothing or coverings for religious or cultural reasons, older adults living in residential care facilities with limited mobility, those with darker skin or living in the South Island of New Zealand and anyone with limited sun exposure may require supplementation, particularly during winter months. 

Vitamin D is best absorbed when taken with a meal with a small amount of fat; however, a high-fat meal decreases absorption.

Vitamin D is essential for bone health, to help prevent osteoperosis and fractures, particularly in older adults. Some medications can lead to thinner bones and a risk of osteoporosis so it can be a good idea to chat to your GP or specialist to find out whether vitamin D might be a good idea to prevent any future complications. 

Vitamin D may also have anti-inflammatory effects and is important for the proper functioning of our immune system.

There is potential for Vitamin D to aid with pain and lack of function in people with fibromyalgia and arthritis, but further evidence is still needed. 

The upper level of vitamin D in Aotearoa New Zealand and Australia for anyone one year and older is 80µg/day, or 3200 IU. Vitamin D is stored in the body for a long time, so high doses (over 4000IU per day) of vitamin D from supplements taken over a long period of time can cause vitamin D toxicity, leading to high levels of calcium in the body (hypercalcaemia). This can manifest in several health issues, such as weakening bones, kidney stones, and interfering with heart function.

Vitamin D deficiency is more likely to occur in winter when people don’t go outside as often and wear more clothes that cover their skin. With regular sun exposure in summer, people under the age of 50 can make and store enough vitamin D for six months, which can carry them through winter. People over the age of 50 have a reduced ability to make and store vitamin D, so they may need to supplement over the winter months.

People who, for religious or other reasons, cover up most of their skin whenever they are outside won’t be able to produce enough vitamin D and will likely need to take a supplement.

People with dark skin need more time in the sun than those with fair skin to make adequate amounts of vitamin D. It is estimated that for older women with fair skin, exposure of 6% of the body (face, hands, and forearm) to sunlight for 15-30 minutes, 2-3 times per week would make the equivalent of 15 µg of vitamin D a day.

Those living in the South Island of New Zealand, anyone with limited sun exposure, and anyone who is housebound may also require supplementation. 

Talk to your doctor if you think you might not be getting enough vitamin D and would like to look at vitamin D supplementation. 

It is made primarily in the skin through sun exposure, however it is also found in small amounts in foods. 

• Food sources: cod liver oil, oily fish (such as salmon, herring and mackerel), eggs, fortified dairy products and plant milks. Fun fact: mushrooms contain a small amount of vitamin D, but this can be increased by exposing them to sunlight!
• Supplements: you can get a prescription through your GP and purchase from pharmacies, supermarkets, online or health stores

Calcium is an essential mineral that plays a vital role in preserving sturdy bones and teeth, regulating muscle movements, transmitting nerve signals, and facilitating the release of important hormones and enzymes. It is primarily stored in the teeth and bones, providing structure and strength.

The recommended daily intake for children and adolescents varies between 500 - 1300mg per day depending on age and gender. Men aged 19-70 years and women aged 19-50 years are recommended to have 1000mg of calcium per day through food sources. Men over 70 years of age and women aged 51 years and above have increased needs of 1300mg per day. Calcium can be obtained from various sources and should be consumed ideally through food. If you are not reaching the recommended daily intake through food a calcium supplement can be a way to top up your calcium intake. 

You can supplement any time of the day, preferably with food to aid absorption.

The upper level of intake for calcium from all sources is 2500mg per day for anyone aged 1 year and above. High calcium intake is a concern for those who suffer from kidney stones, so it is important to check with your doctor before starting or increasing calcium supplementation. 

Inflammatory arthritis conditions such as rheumatoid arthritis and some medications used in treating these conditions can increase your risk of developing osteoporosis. Calcium can help to reduce the risk of developing osteoporosis in older age, and helps to keep bones and teeth strong and healthy.

New Zealand adults’ average intake is about 850 mg daily, so make sure you include calcium-rich foods in your diet.

During menopause, there is an increased risk of bone fractures and osteoporosis, so it is especially important to ensure you are consuming enough calcium through your diet during this time.

The upper level of calcium intake for anyone aged 1 year and above is 2500mg per day. Too much calcium can interfere with the absorption of other minerals such as iron and zinc, cause constipation, and can cause kidney problems. High doses of calcium supplements have also been linked to cardiac issues.

Calcium supplements aren’t for everyone, so you should consult your doctor before supplementing.

Getting calcium from foods is the best way to ensure you get enough calcium. However, those on a vegan or vegetarian diet or who don’t consume dairy products may need to consider taking a calcium supplement. But there are ways to design your diet to maximise absorption of calcium. 

Those at higher risk of osteoporosis may also need to consider taking a calcium supplement.

If you think you might need to take a calcium supplement, talk to your doctor first.

• Food sources: dairy and dairy products (such as milk, yoghurt and cheese), bony fish (tinned sardines or salmon), mussels, legumes, almonds, soy products, sesame seeds, whole grains, dark leafy greens, and calcium-fortified plant milks.

You can buy supplements from pharmacies, health stores, supermarkets and online, or get a prescription from your doctor.